Stacked fluted-wall receptacles



" Aug. 12, 1969 F. c. STAKEL 3,460,670

STACKED FLUTED-WALL RECEPTACLES Filed Jan. 21, 1965 2 Sheets-Sheet 1INVENTOR /cfafE/cA/CISrm/a ATTORNEY Aug; 12, 1969 F. C. STAKEL 3,460,670

` STACED FLUTED-WALL RCEPTACLES Filed Jan 21, 1965 2 sheets-sheet 2*"uuu -l figg, 8.

6 1 fa 6 "nl" ATTORNEY United States Patent Utilice 3,460,670 PatentedAug. 12, 1969 3,460,670 STACKED FLUTED-WALL RECEPTACLES Frederick C.Stakel, 31 Ramhorne Road, New Canaan, Conn. 06840 Filed Jan. 21, 1965,Ser. No. 426,918 Int. Cl. B65d 85/60 U.S. Cl. 206-65 2 Claims ABSTRACTOF THE DISCLOSURE Nested stacks of concave uted Wall cup-shapedreceptacles such as baking cups, candy cups and the like, die formedfrom stacked layers of non-adherent sheet material, incorporating atleast one layer, and optionally having each alternate layer, formed ofmetallic foil, providing a stiif, moisture-resisting assembly tending toavoid the flattening sagging encountered with nested fluted paper cups,and processes for producing these nested stacked receptacles.

This invention relates to stacked tinted-wall receptacles, such as cups,trays, candy cups and the like, and particularly to the fluted bakingcups fabricated, packed and sold in stacks, to be separated and used bythe ultimate consumer.

Conventional baking cups, particularly those formed of thin fluted paperor like material, exhibit extremely poor shape-retentioncharacteristics. Such iluted receptables are concave by virtue of thetapered, corrugated flutes accordion-pleating their peripheries intoupstanding uted walls. With the passage of time, such stacked flutedpaper baking cups generally tend to return to the original configurationof the thin sheet webs from which they are initially stamped. Such cupstend to spread, and they take the peripheral shape of the hexagonalpackages in which they are generally packed. Conventional baking cupsmust be supported in the cavities of muffin tins before they can be lledwith batter if they are expected to retain their shape during baking.

The sagging and flattening of fluted paper receptacles, such as paperbaking cups and candy cups, is caused either by their absorption ofwater vapor or moisture, or by their resilient memory of their originalsheet congurati'on which produces a gradual flattening return to thisconfiguration with the passage of time, or merely by their inherent lackof stiffness and rigidity.

When sheet metal such as aluminum foil is formed into a fluted cup ortray shape, it is stressed beyond its elastic limit in the region of theflutes and accordingly exhibits no tendency to return to its originalflat sheet form. Furthermore, such metallic foil does not absorb waterVapor from the atmosphere, and damp atmospheres produce no sagging orloss of shape in fluted metal foil cups.

The attractive appearance and good shape-retention of thin metallic foilmake it a highly desirable material for iluted serving trays, candy cupsand the like, and its good heat transmission characteristics make it anexcellent material for disposable cooking receptacles such as bakingcups. However, the fabrication of thin metallic sheet material intocup-like shapes has been prevented in the past by several manufacturingproblems. Thick foil plates and pans can be stamped, fluted or formed inthe desired shapes from such material as aluminum foil from 0.002 to0.005l thick, for example, but they are too expensive to use asdisposable trays or baking cups. Suitably thin metallic foil, less than0.002 in thickness for example, generally tears when stamped into utedcup configuration since the high stresses produced by the fluting diesare concentrated in the bends or infiexions bounding the flutes.Furthermore, it has been impractical to stamp stacked metallic foilsheets into stacks of fluted cups because of the swaging or jammingtogether of the resulting cups, making it impossible to separate themfrom the fluting dies or from each other without tearing.

Accordingly, it is an object of the invention to provide methods for thefabrication of iluted receptacles tending to maintain them in theirfluted concave configuration until they are used by the consumer.

Another object is to provide stacks of fluted cups which are unaffectedby water vapor in the ambient atmosphere.

A further object is to provide methods for the production of flutedbaking cups which may be used on baking sheets, without any need forrecessed-cavity mufiin tins.

Another object is to provide methods for the production of fluted cupsfrom thin sheet metallic foil.

A further object is to provide methods for the production of unitarystacks of uted cups which are capable of easy separation by the user,with one or more of the cups in each stack being formed of thin metallicfoil.

Another object is to provide a combination food package incorporating afood product, baking cups and a baking sheet in a single, convenientdisposable package.

Other and more specific objects will be apparent from the features,elements, combinations and operating procedures disclosed in thefollowing detailed description and shown in the drawings, in which:

FIGURE 1 is a schematic side elevation view, partially in section,showing the forming station of production apparatus employed in theprocesses of the present invention, with juxtaposed webs passing througha fluting die assembly;

FIGURES 2, 3 and 4 are fragmentary enlarged, crosssectional sideelevation views of the uting die assembly of FIGURE l, showing threesuccessive positions of the fluting dies employed in producing cupsaccording to the present invention;

FIGURE 5 is a side elevation vieW, partially in section, of a stack offluted cups formed by the processes of the present invention;

FIGURE 5A is an enlarged fragmentary cross-sectional side elevation Viewof a portion of the stack of cups shown in FIGURE 5;

FIGURE 6` is a similar enlarged fragmentary crosssectional sideelevation view of a stack of cups produced by another process of thepresent invention;

FIGURE 7 is a perspective view of a package incorporating features ofthe prsent invention, partially disassembled; and

FIGURE 8 is a schematic plan view showing a portion of the package ofFIGURE 7 unrolled, attened and used as a unitary baking sheet.

Fluting die assembly The stamping dies employed in producing unitarystacks of fluted receptacles by the methods of the present invention areillustrated in FIGURES 1 through 4. As shown in FIGURE l, a number ofstrips or webs 20 of the materials from which each nested stack offluted cups is to be formed are drawn from reels 22 past tensioningrollers 24 and one or more aligning guide rollers if desired (not shown)into face-to-face juxtaposition between capstan means such as the pinchrollers 26.

The pinch rollers 26 provide longitudinal driving force drawing thestrips endwise from reels 22, and the juxtaposed strips are thus urgedforwardly, preferably continuously, into the cutting and fluting dieassembly 28 shown in the enlarged fragmentary sectional views of FIGURES2, 3 and 4.

During each operating cycle of the die assembly 28, the telescopingfluting dies sever a stack of sections from the juxtaposed strips 20,and form them into a nested stack 30 of fluted-wall receptacles such asthe baking cups shown in the drawings.

Web materials As shown in FIGURES 5A and 6, the unitary stacks 30 ofuted receptacles formed by the methods of the present invention allincorporate at least one receptacle, preferably the next to theoutermost one, which is formed of thin metallic foil. In the enlargedsectional side elevation view of FIGURE 5A the next to the outermost cup32 is formed of thin metallic foil, preferably from 0.0007" to 0.0010 inthickness, In the similar enlarged sectional side elevation view ofFIGURE 6, the next t the outermost cup 32 and each cup 38 alternatelystacked inwardly throughout the entire stack 30 of iiuted cups is formedof thin sheet metallic foil material, with both the innermost andoutermost cups 40 and 36, and all of the remaining interleaved cups 42being formed of paper or other porous material.

When at least one of the stacked cups, such as the next to the outsidecup 32, is formed of metallic foil material, as shown in FIGURE A, theentire stack of cups is maintained in its concave configuration by thestiifening and reinforcing effect of this single foil cup. When thestack 30 is stored on a shelf above a kitchen sink or stove and thusexposed to warm, moist, rising air, such a foil cup 32 impedes orprevents the absorption of water vapor passing from the outside of thestack of nested cups toward its center.

In the stack of fiuted cups shown in FIGURE 6, where each second cup 32and 38 is formed of thin metallic foil, all of these foil cups have adesirable stiifening and reinforcing effect tending to retain all of thenested cups in their fluted cup shape. These interleaved metallic foilcups also prevent the absorption of water vapor from the atmosphere byany of the non-metallic cups interleaved between them, since only theedges of the interleaved non-metallic cups are exposed to water vapor inthe atmosphere.

Thus, in the cups stacks 30 of both FIGURES 5A and 6, the outernon-metallic cup 36 and the next outermost metallic foil cup 32 form theoutermost portions of both stacks. In the stack of FIGURE 5A, all of theremaining cups are formed of non-metallic and preferably porous materialsuch as 27-pound paper, impregnated with a low friction impregnant suchas dry wax to increase its weight to that of 3G-pound paper, forexample. In the interleaved stack shown in FIGURE 6, the outermost cup36 and the innermost cup 40 are both formed of such non-metallic sheetmaterial, while the remaining cups between these two cups 36 and 40 areformed alternately of foil cups 32 or 38 and of nonmetallic cups 42.

Aluminum foil between 0.0007" and 0.0010" thick is well suited to formcups 32 and 38, and may be colorcoated in many bright attractive colors.Foils of other metals and alloys may be used if desired.

The non-metallic sheet material such as porous waximpregnated paper,forming layers 34, 36, 40 and 42, acts as a low-friction layerinterposed between each layer of metallic foil and the adjacent metalsurface of the uting die or of another foil layer. These low-frictionlayers thus guide and facilitate the sliding surface readjustment of thefoil layers during the fluting operation, while also blocking anytendency of the metallic foil to swage, curl or adhere to any adjacentmetal surface.

If desired, these low-friction layers may be formed as coatings ofTeilen (polytetrauoroethylene), or silicones or similar low-frictionmaterials applied directly to the surfaces of the metallic foil layers.However, interleaved layers of Wax-impregnated paper have been found tocombine the advantages of low friction with blocking deflection ofcurling ridges of the foil layers, airmatively preventing undesiredlocking or swaging of adjacent foil regions with each otheror with thelluting die surfaces.

Heating of the stacks 30 following the iluting operation appears toproduce a setting of the wax impregnant in porous layers 34 and 36;acting together with the stiffening and moisture barrier effect of thelirst foil cup 32, the stacks 30 maintain their original shape, and donot spread into the hexagonal or square shape of any container whichconnes them.

In the bulk packing of such nested stacks of baking cups for use bycommercial bakeries, packing tubes and cylinders are not required forthe stacked baking cups of this invention because of their long-termshape retention characteristics, producing substantial economies inpackaging labor and materials.

Severing and flute forming The successive views of FIGURES 2, 3 and 4show the severing and ilute forming die assembly 28 in three successivepositions occurring during each operating cycle of the die assembly. Afixed socket die 46 and a die housing 49 guiding movable telescoping diemembers 48, 50 and 52 form the two halves of the die assembly 28. Thepinch rollers 26 may revolve intermittently between cycles of dieassembly 28, but they preferably revolve continuously, causing constantforward feed motion of the juxtaposed strips 20 as they approach the dieassembly 28. The closing of the two halves 46 and 49 of the die assembly28 during each cycle halts the forward progress of the strips 20therethrough. This produces the sidewise buckling 21 shown in FIGURE luntil the die assembly 28 opens at the end of its cycle. After the dieassembly 28 opens, the juxtaposed strips 20 will drop between the halvesof the die assembly 28 by the force of gravity, bringing them intoposition for the next fluting cycle.

This is the condition shown in FIGURE Z, where the juxtaposed strips orwebs 20 are positioned between the open halves 46 and 49 of the dieassembly 28. As the die assembly 28 begins to close, these strips 20 areurged to the right by an anvil 48, mounted in the die housing 49 facingthe socket die 46, against the sharpened edge of a ring-shaped severingblade 44. This blade 44 is positioned by an adjustable backing wedgering 45 in the round periphery of the concavely tapered or horn-shapedsocket die 46. Anvil 48 is moved toward severing blade 44 until thecentral circular sections 29 of all of the strips 20 are severed by theblade 44, as suggested in FIGURE 3, forming a stack of correspondinglyshaped juxtaposed layer sections 29 aligned symmetrically with thecenterline axis 27 of the die assembly 28. The anvil 48 is formed as atubular member having a flat end conforming substantially to the shapeof ring-shaped severing blade 44, and in its extended position anvil 48bears against the sharp edge of severing blade 44 to provide thesevering action desired. If desired, anvil 48 may be provided with aring-shaped recess or step aligned for telescoping overlapping withblade 44 to provide positive shearing of sections 29 from strips 20.

Within the ring-shaped anvil 48 is positioned a telescopingly movablering die 50 with a chamfered or S- curved fluting die surface 51 facingthe cavity of the socket die 46. A telescoping ram 52 is positionedwithin the ring die 50, and as shown in FIGURE 2 the ram 52 is providedwith a substantially flat leading edge and a tapered fluted side wall.This chamfered iluted surface 51 of ring die 50 iits within an incurvingportal portion 54 of the socket die 46 (FIGURE 3), while the flutedtapered sidewall of the ram 52 fits within the liuting cavity portion 56of the concave socket die 46, as illustrated in FIGURES 3 and 4.

The socket die 46 therefore provides a smoothly converging formingpassage with longitudinally extending wavy or corrugated flutes matingwith those of ring die 50 and ram 52, and extending from the rim ofincurving portal portion 54 through fluting cavity 56 to a deliveryaperture 57 forming the exit of die 46, opening into a delivery conduit58 (FIGURE 3).

As shown in FIGURES 3 and 4, the cup forming operation is performedprimarily by the telescoping ram 52 moving out of ring die 50 toward theiluted hollow cavity 56 in the socket die 46 depressing the centralportion of the severed juxtaposed layer sections 29 toward the rearaperture of the socket die 46.

The wall-liutimg operation forming tapered corrugated flutes in thewalls of the resulting nested stacked cups 30 is performed initially bythe co-action of the ring die 50 with portal section 54 of the socketdie 46. The corrugated chamfered iluting die surface 51 of ring die 50interts with the corrugated portal surface 54 of socket die 46, forminga converging conical aperture with increasingly deep wavy corrugationsthrough which the peripheral walls of the severed layer sections slideedgewise while they travel through the die assembly 28, as shown inFIGURE 3. The uted corrugations of the portal section 54 are alignedwith and merge smoothly with the corresponding uted corrugations in theconverging or conically tapered cavity portion 56 of socket die 46. Thusthe movement of ram 52 urging the central portions of the juxtaposedlayer sections progressively through successive diametral planes of thesocket die 46 draws the peripheral walls of the juxtaposed layersections 29 through the corrugated passage bounded by ring l die 50 andportal S4 to urge these peripheral walls of the juxtaposed layersections inwardly, from their original radial position in the same planewith the central portions of the layer sections 29, toward theirstanding fluted side wall position indicated in FIGURE 5, in which theyform the uted walls of the nested stacked cup-shaped receptacles.

As the ram 52 continues its passage through fiutng die 46, the sidewalls are drawn progressively closer together and given their finalfluted shape by being drawn between the corrugated utes in the taperedcavity portion 56 of fluting ldie 46 and the corresponding iluted ridgesand depressions on the side walls of ram 52. This final wall ilutingaction occurs as the ram moves from the position shown in FIGURE 3toward the delivery position shown in FIGURE 4, where the nested stack30 of fluted-Wall concave cups has been drawn entirely through the utingdie and ejected through its delivery aperture 57 into delivery conduit58.

Heating of formed stacks Each nested stack 30 of fluted cup-shapedreceptacles delivered by the luting -die assembly 28 is ejected directlyinto the delivery conduit 58 shown in FIGURES 1-4, which has an internaldiameter slightly larger than the diameter of delivery aperture 57(FIGURE 3). The nested uted stacks 30 pass successively along andthrough the conduit 58, which acts to confine their outer peripheriesand thus maintains them in their nested condition, aided by theirjuxtaposition with the other stacks 30 successively formed by eachoperating cycle of die assembly 28.

The natural resilience of each nested stack ejected by the die assembly28 produces a slight expansion of the rims of each nested stack as it isejected through aperture 57, and this expansion brings its outerperiphery into contact with the interior wall of conduit 58,andrprevents the stack from being drawn back into the tiuting die 46 asram 52 withdraws from the ejection position shown in FIGURE 4 toward theinitial position shown in FIG- URE 2, to begin the next cycle. Theresilient engagement of the wall rims of each ejected stack of cups 30with the wall of conduit 58 maintains the stack in the transverseorientation shown in FIGURE 2 after its ejection from the die assembly28 and each ejected stack is moved along the delivery conduit 58 by theejection of each succeeding stack 30, as indicated in FIG. 1.

As the stacks of fluted cups are moved down the delivery conduit 58,they pass within a heating zone therein produced by a heater 60 formedfor example of Calrod heating elements connected to a suitable powersource and enclosed within an insulating jacket of asbestos or othermaterial to prevent injuries to onlookers.

The action of the heating zone produced by the heater 60 is believed to`be two-fold: the heating of the fluted stacks of cups apparentlytoughens the metallic foil, changing its grain structure slightly toalleviate any residual stress caused by the iluting operation. Inaddition, in the fluted regions of each stack, the heating of the waximpregnant in the paper layers interleaved between the metallic foillayers, coupled with the subsequent cooling of the stack, apparently hasthe eiect of setting the interleaved paper cup-shaped sections in theirluted cup configuration, possibly by softening and then hardenin g thewax impregnant.

The overall effect of the passage of the uted stacks 30 through thisheating zone therefore appears to be to relieve internal stresses and tominimize the resilient memory of the uted cups so they no longer tend tospread and atten toward their original flat sheet configuration. Thecups thus maintain themselves neatly nested in the stacks ejected by thefluting die assembly.

Combination package A combined package is shown in FIGURE 7,incorporation a stack of cups 72 witth a block oi pre-mixed andready-to-bake baking dough enclosed in a single outer container whichmay be used both for storage and as a baking sheet. In this combinedpackage the outer cover 62 is formed of a heat resistant central papercore 64 covered on both sides by metallic foil layers 66, and is rolledto form a cylinder with a seam 67 joined by heat or suitable adhesivesto enclose the contents of the container. The ends of the cylinder areenclosed by end caps 68 and 70, shown with crimped, milk bottle cap typeend closures in FIGURE 7. The caps 68 and 70 may also be formed as metaldisks with their rims crimped over the ends of the cover 62.

As shown in FIGURE 7, a stack of tluted baking cups 72 is positioned inone end of the cylinder formed lby the rolled cover 62. The remainder ofthe cylinder is normally lled by a block of pre-mixed and ready-tobakebaking dough, for use in baking rolls, cup cakes, muiins or the like.

As shown in FIGURE 8, the outer cover 62 may be unrolled and flattenedafter the package is opened, and the flattened cover 62 may be used as:a baking sheet on which the stacked baking cups of the stack 72 may beunstacked yand arranged as shown in FIGURE 8. The ready-to-bake dough inthe remainder of the package may then be placed in the baking cups,which provide with baking sheet 62 an easily usable and disposablepackage for both storing and baking of the contents.

The metallic foil cups of this invention are unusually well adapted foruse in this combination package, since their shape retentioncharacteristics eliminate the need for recess-cavity muin tins and allowthem to be used alone on baking sheets such as the sheet formed by thecover 62.

I claim:

1. A nested stack of concave, uted-wall cup-shaped receptacles formed ofjuxtaposed layers of sheet material, each formed layer incorporating abottom Wall and a uted side wall in which the ilutes of each layer aredie-formed and conform in nested relation with the iiutes of the nextadjacent layers, each layer constituting an individual, non-adherentreceptacle being independently separable from the stack, with at leastone receptacle comprising a layer of metallic foil and with at least thenext layers adjacent to the inner and outer sides of said one metallicfoil layer comprising non-metallic lowfriction material, there being aplurality of receptacles embraced by said one metallic foil receptacle.

2. The nested stack of receptacles defined in claim 1 wherein themetallic foil receptacle forms a surrounding stiifener and moisturebarrier for the remaining embraced receptacles of the stack retardingthe passage of 3,078,006 2/ 1963 Price e't al. 220-64 moisture throughthe non-metallic, low friction material. 3,143,241 8/ 1964 Howell220'-'64 3,165,201 1/ 1965 Woodman 206-'-5` 6 References Cited rtWILLIAM T. DIXON, JR.,`Primary Examiner UNITED STATES PATENTS 51,574,259 2/1926 Sarfr 220-65 Us, @1 XR 2,218,388 10/1940 Twombly 206-652,407,118 9/1946 Waters 22o- 65 99-172; 2210-64, 97,; 229-1, 3

2,947,441 8/1960 Brannan 22o- 63

